free hit
drdoom's Content - The Lotus Forums - Official Lotus Community Partner Jump to content


Full Forum Member (FFM)
  • Posts

  • Joined

  • Last visited

  • Days Won


Posts posted by drdoom

  1. Seems we are generally inclined to crave miracle cures, hence the appetites for fuel and oil additives. How many have gleaned the parallel between oil flush liquids and laxatives, for example? A great deal of discussion continues to be devoted to the question of oils in various fora, lately offering up one or two finer points that had not previously occurred to me. First: that heavier oils are more difficult to de-aerate, something track day inclined operators might want to consider. Second: one valuable facet inherent in the better synthetic oils is resistance to burn-off or evaporation, very pertinent to lubrication of the rings near TDC when hydrodynamic action goes null, local temperatures are high, and boundary lubrication is critical.

    The Lucas oil additive clearly makes treated oil visibly more viscous, appealing to the eye but perhaps counterproductive in some applications. As to fuel additives, we are wise to consider how much technology has been worked through in order to arrive at the cocktails we know as petrol.


  2. Always worth minding that low oil pressure at idle is not a vital indicator of the state of things in most cases. There is nothing going on which requires substantial pressure at idle. Still, one is wise to be vigilant on the state of things end-end in a Lotus. Critical targets for oil pressure have been framed by Tony Rudd, who knew the engine most thoroughly, and I recall these being a minimum value ( sorry, not recalled ) at idle then rising 10 PSI per 1000 RPM to a minimum of 45 peak. That describes the parameters around which the 900 Series were designed.


    • Like 1
  3. Right, agree on Thackery's preferred over the cushions and we should ever be mindful that just because replacement bits are offered by our faithful suppliers does not ensure they are up to spec in all instances. No where will one see the Durometer figures for hardness of rubber components listed, something obviously altogether pertinent to effectiveness in a given application.

    There now exist alternative cushioning elements in the form of stainless steel wire clumps, some of which may afford a solution for our classic cars, here or there. Link attached.


  4. I've heard many accounts over the years of owners running carbs of this form with tight or solid mountings and none reporting the froth related concerns published. Not a scientifically derived conclusion, but consistently reported anecdotally. There can be be no tolerance of fuel leaks in this application as Esprit in numbers are no longer with us due to catastrophic fire loss. With such significant leakage I'd double back on floats condition and fuel pressure setting, just to be careful. Running DCOE's on my Elan for years over long distance journeys, urban jaunts and track day outings it was my experience that the Thackery's were better than the rubber bits, and that it was best to have things pulled up tighter than the printed dogma, as air leakage arose otherwise. FWIW

    • Like 2
  • Create New...